A method for the measurement of the properties of individual electrode-skin interfaces and the implications of the electrode properties for preamplifier design

A method to measure impedances of individual electrodes has been developed. The DC- and AC-loading conditions of the electrode can be varied in a large range. Impedance values of electrodes on unprepared or alcohol rubbed skin are measured to be very high and vary between electrodes both on the same test person and on different test persons. This leads to important consequences for interference reduction and current noise properties of the bioelectric amplifier.